[SamReidHughes]

Maybe. For stuff like the personal notes you're keeping on a criminal conspiracy, a flash drive might be fine. But I'd be very skeptical of storing, say, the PHP source code to the Silk Road on a flash drive or SSD, because the internal data structures of the SSD could leak information about the sizes of individual files. If the feds can recover the sizes of individual files, rounded up to the next multiple of 4K, and you've got the PHP source code for the Silk Road stored there, it's game over. The same goes for filesystem encryption, like the kind ZFS (I think) has.

(I'm not personally familiar with ZFS, but the ZFS docs, especially https://docs.oracle.com/cd/E26502_01/html/E29007/gkkih.html#... really creep me with regard to this. The last thing you'd want is blocks in your local encrypted copy of PHP source code to be compressed first. And so then you'd think you'd want encryption enabled on a pool, but from reading the docs it seems that feature merely makes the filesystems on that pool inherit that encryption option, instead of doing some sort of filesystem-blind block-level encryption, where there's any variance in the encryption of blocks, or any information that could be derived from locations of blocks. So I think the suggestion to encrypt on a directory-by-directory basis to limit your exposure is not a very good one. I'd recommend that you use a spinning hard drive, whole disk encryption of the sort we have today, take out the battery, and keep your foot by the power outlet.)